Cut-off of the Physical Performance Test to detect functional status impairment and mortality risk in interstitial lung disease

Functional status (FS) is a key outcome in people with interstitial lung disease (ILD). Physical Performance Test (PPT) is a FS measure. However, cut-off points to determine FS impairment and mortality risk as estimated by the 6-minute walk test (6MWT) with the PPT in people with ILD are lacking. This study explored thresholds of PPT to identify FS impairment and mortality risk in people with ILD. A cross-sectional study was conducted. FS was assessed with the PPT, short (PPT-28) and long (PPT-36) versions. FS impairment was defined as a 6MWT of less than 70% of the predicted value. Cut-offs of 6MWT for mortality risk (250, 330 and 350m) were also explored. Optimal cut-off values were determined based on the highest Youden index in receiver operating characteristic (ROC) analysis. 85 people with ILD were included (68±11 years; 53% male; FVCpp 81±22; DLCOpp 57±21). A cut-off of <19.5 for PPT-28 identified FS impairment and mortality risk across all 6MWT cut-offs. For PPT-36, a cut-off of <28.5 detected FS impairment, while <27.5 (6MWT<350m) and <26.5 (6MWT<330m and <250m) identified mortality risk. In ILD, cut-off values of <19.5 for PPT-28 and <28.5 and <26.5 for PPT-36 may be used to detect FS impairment and mortality risk as estimated by the 6MWT, respectively. This information can now be used to provide tailored interventions. <fig><object-id>erj;66/suppl_69/PA674/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>